package org.ucas.faker.web.utils;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class StringUtils {

  /**
   * 下划线转驼峰法
   * @param line 源字符串
   * @param smallCamel 大小驼峰,是否为小驼峰
   * @return 转换后的字符串
   */
  public static String underline2Camel(String line,boolean smallCamel){
    if(line==null||"".equals(line)){
      return "";
    }
    StringBuffer sb=new StringBuffer();
    Pattern pattern=Pattern.compile("([A-Za-z\\d]+)(_)?");
    Matcher matcher=pattern.matcher(line);
    while(matcher.find()){
      String word=matcher.group();
      sb.append(smallCamel&&matcher.start()==0?Character.toLowerCase(word.charAt(0)):Character.toUpperCase(word.charAt(0)));
      int index=word.lastIndexOf('_');
      if(index>0){
        sb.append(word.substring(1, index).toLowerCase());
      }else{
        sb.append(word.substring(1).toLowerCase());
      }
    }
    return sb.toString();
  }
  /**
   * 驼峰法转下划线
   * @param line 源字符串
   * @return 转换后的字符串
   */
  public static String camel2Underline(String line){
    if(line==null||"".equals(line)){
      return "";
    }
    line=String.valueOf(line.charAt(0)).toUpperCase().concat(line.substring(1));
    StringBuffer sb=new StringBuffer();
    Pattern pattern=Pattern.compile("[A-Z]([a-z\\d]+)?");
    Matcher matcher=pattern.matcher(line);
    while(matcher.find()){
      String word=matcher.group();
      sb.append(word.toUpperCase());
      sb.append(matcher.end()==line.length()?"":"_");
    }
    return sb.toString().toLowerCase();
  }
}
